Refrigerating apparatus



Nov. 1, 1932; I w, 1511 1 1 8865331 REFRIGERATING APPARATUS Filed May 30, 1928 2 Sheets-Sheet l N 9 M. w. FISH 1,886,331

REFRIGERATING APPARATUS Filed May 30, 1928 2 ShBQtS ShEGt 2.

15 gww/ntoz wwm 75w Patented Nov. 1, 1932' UNITED STATES PATENT OFFICE MORTIMER W. FISH, OF DAYTON, OHIO, ASSIGNOR TO FRIGIDAIRE CORPORATION, OF DAYTON, OHIO, A CORPORATION OF DELAWARE REFRIGERATING APPARATUS Application filed May 30,

This invention relates to improvements in refrigerating apparatus and more particularly to means for controlling the starting and stopping of an electric motor for driving such apparatus. 7

An object of this invention is to provide a snap switch for starting and stopping an electric motor of a refrigerating machine which switch is adapted to carry loads larger 19 than necessary on the usual household type of refrigerating machines.

Another object of this invention is to provide a snap switch for starting and stopping an electric motor or the like, the snap acting mechanism being adapted to maintain a. rigid connection between electrical contact points.

' Another object of this invention is to provide an attachment for a standard single- 20 pole switch used in the usual household type of refrigerating machines, which attachment renders the single-pole switch capable of use as a double-pole switch.

Another object of this invention is to provide a snap switch for a refrigerating system which is adapted to eliminate the relay magnetic switch ordinarily used for doublepole switch equipment.

Further objects and advantages of the present invention will be apparent from the following description, reference being had to the accompanying drawings, wherein a preferred form of the present invention is clearly shown.

In the drawings:

Fig. 1 is a side elevation of a switch embodying features of my invention;

Fig. 2 is a cross-section of a portion of the switch shown in Fig. 1 with the elements '40 in a different position;

Fig. 3 is a view similar to Fig. 2 with the elements in the position shown in Fig- 1;

Fig. 4 is a top plan view of Fig. 1;

Fig. 5 is a top plan view of a portion of '45 the attachment; and

Fig. 6 is a diagrammatic view-of a refrigerating system embodying features of my invention.

Heretoforein installations of automatical- 30 ly actuated refrigerating systems, it has been 1928. Serial No. 281,603.

customary to use a single-pole switch for starting and stopping the motor. Under certain conditions it has been necessary to install a double-pole switch where the load on the motor is too great for a single-pole switch. However, as heretofore installed, it has been customary to use the single-pole switch as a relay control for a magnetic double-pole switch. It is contemplated by this invention to eliminate such relay systems in the manner hereinafter described.

Arefrigerating system which may embody features of invention may comprise a compressor 41 discharging compressed refrigerant through a pipe 43 to a condenser 44. Re-

frigerant condensed in such condenser may be stored in a receiver 45. Liquid refrigerant from receiver 45 is admitted through the plpe 46 into the evaporator 47 by means of a floatcontrolled valve, not shown, in the evaporator at the end of pipe 46. The refrigerant evaporated in the evaporator 47 returns through the pipes 51 and 49 to the compressor 41 preferably through the crankcase. The evaporator 47 may have depending coils 48 in order to increase the refrigerating area of the evaporator. starting and stopping of the motor 42 which drives the compressor 41, an expansible bellows 21 may be connected to the pipes 49 and .51 by means of the pipe 50. The expansible bellows 21 operates the snap switch, hereinafter more fully to be described, in order to open and close the contacts 10 and 11 connected to the two wires leading to the motor 42.

The snap switch used in such a system is more fully disclosed in the other figures of the drawings. The switch may be mounted on a base 100 having, preferably integrally therewith, legs 101. On the base 100 may be mounted the expansible bellows 21. The bellows 21 may have at its lower end suitable connections for'connecting the bellows with the pipe 50. Over the bellows 21, may be provided an elevated platform 102 supported by legs 103, surrounding the bellows, which may be secured to the base 100 in any suitable manner. The platform 102 may be provided with suitable means for supporting a lever In order to control the q arm Such means may comprise upwaidly extending ears 104 through which a pin 23 may extend which pin may be held in position'b'y any suitable means such as the cotterpin shown. The arm 20 may be pivoted on the pin 23-and it may be held in position on the pin by suitable sleeves 105, 106 and nuts 107 which have threaded engagement with the sleeve 106. The upper end of the bellows 21 may be provided with upwardly extending ears 108 through which the pin 22 may pass. This pin 22 may also pass through the arm 20. Thus it isseen that the expansion and contraction of the bellows 21 pivots the arm 20 about the .pin 23.

The bellows 21 has a natural resiliency, but inthe process of manufacture, various bellows may not have the same degree of resiliency. In order to compensate for any such difference in resiliency, a rod 109 may be pivoted on the arm 20 by means of the pin 33 which passes through 'the pivot end of the rod 109 above the threaded portion 32 of the rod. A spring 34 may be interposed between the nuts mounted on the threaded portion 32 and the base 100 and another spring 34 may be interposed between the nuts 35' and the base 100. It is thus seen that by the ad justment of the nuts 35 and 35the tension on the arm 20 may be adjusted to any desired extent.

The end of the arm 20 cooperates with the arm 27 pivoted by means of pin 28 to the arm 20. The arm 27 may comprise two similar pieces straddling the arm 20 and may be rigidly held together by riveted spacers, as shown. The end of the arm 27 is provided with a cam surface 29 which rides on a roller 31 mounted on the pivoted bracket 31 urged wardly b means of the roller 31. The cam 29 may a so serve as a spacer for the similar pieces forming the main portion of arm 27.

Above the end piece 36 of the arm 20 1s.

' mounted a spring device comprising in general a pin 37 urged downwardly by means of the spring 38, the tension of which may be adjusted by means of the hollow nut 39. This spring device may be mounted on the U-shaped platform 110 mounted on the platform 100. I

The portions heretofore described are, in general, used as a standard equipment for a single-pole switchaof a well-known household refrigerating apparatus. Inorder to render this standard single-pole switch available for use as a double-pole switch, I use the following double-pole attachment, In general, the attachment includes a base 40 made of insulating material. The base 40 has upwardly extending flanges 41 which may be secured to thebase 100 by screws or the like. Between the flanges 41 may be supported a toggle mechanism which, in general, com

downward movement of the toggle mechanism is arrested by an upwardly directed projection 40'. Pivoted at the upper edge of the flanges 41 by means of"pin 24, is a swinging lever 24 which has its lower end pivoted to the link 25. This lever 24 may have a U-shaped horizontal cross-section and may have a notch bent in it to accommodate a cross member 12 of insulating material. This cross member 12 may be secured to the lever 24 by means of screws or the like. At the ends of the cross member 12 may be mounted the contact pieces 10 and 11 on the underside of which may be provided silver contact points 10 and 11' adapted to contact with silver points 10 and 11 respectively.

The contact points 10" and 11" may be mounted on' extensions 40" of the base 40 and may have suitable leads to the connecting posts 14 and 15. Suitable connecting. posts 18 and 19 may be attached to the base 40 and leads 16 and 17 may be carried to the contact arms 10 and 11 preferably by passing the leads through the contact arms and securing them on top of the arms, as clearly shown in Fig. 4, by passing them under tongues cut in the ends of arms 10 and 11 and soldering them in place.

Openings may be provided in the base 40 through which the leads may pass from the switch, the base 100 having an opening 61 therein almost as large as the horizontal extent of the base 40. This is particularly useful if a cover is to be placed over the switch and secured to the base 100.

In operation, when the pressure in the pipes 49 and 50 of the refrigerating apparatus increases sufiiciently to move the arm 20 a certain distance, that the roller 31 will suddenly urge the arm 20 further upwardly and thus suddenly urge the toggle downwardly and close the contacts. This starts the operation of the motor 42and the refrigerant compressing action of the system. When the pressure in the pipes 49 and 50 drops below a certain value the arm 20 descends to the point where the roller 31 urges the arm downwardly by snap action and thus breaks the contacts and stops the operation of the motor 42. The limits of making and breaking may be adjusted independently by means of the cap 39 and the nuts 35 and 35. The independence of adj ustmnt is possible because pressure, a temperature adjustment is se-' cured.

It is to be noted that there is provided an expansible body, such as 21, responsive in movement to variations of temperatures in the refrigerating system. Also there is provided an electrical contact device, which may include either a single or double pole contact switch for making and breaking an electrical circuit which furnishes the energy for the refrigerating system. Also there is provided a snap acting mechanism interposed between said expansible body and said contact device, said snap acting mechanism includes a toggle-like structure which is adapted to provide a very powerful contacting force upon the contacting device or poles. This togglelike structure may include the links 25 and 26 These links are adapted to be in supplemental angular relation when the contact device is closed. That is, the links 25 and 26 are substantially in a straight line when the contact points are brought together, It is to be noted that such a relation of parts produces a very strong force, multiplying the force of the snap action actuating springs many times, theoretically to an infinite extent. This force is transmitted through the rigid spring-like members 10 and 11 to the contact points. This insures a tight and rigid connection between the contact points without the necessity of extremely strong actuating springs.

By the use of the double-pole attachment, it is not necessary to use a relay to operate a magnetic double-pole switch. lhe same standard pressure switch may beused either as a single-pole switch where the load is light, and as a double-pole switch, by the addition of my attachment, when the load is too heavy for a single-pole switch.

While the form of embodiment of the invention as herein disclosed, constitutes a preferred form, it is to be understood that other forms might be adopted, all coming within the scope of the claim which follows.

What is claimed is as follows:

ln a control device, an electrical contact device for making and breaking an electrical circuit, a toggle member for actuating said contact device, a snap acting device connected to actuate said toggle member, said toggle member including two arms in substantial ali nment when the device is closed.

n tGStlIIlOIlYWhGIBOf I hereto afiix my signature.

MORTIMER W. FISH. 

